Welcome to the Monday late afternoon session.

The big picture I will draw tomorrow morning again.

Just for the storyline, we have considered image intensifiers in the context of X-ray imaging.

And today we will talk about flat panel technology.

And what type of preprocessing algorithms are required for flat panels.

So we will discuss the following issues.

First of all I will briefly explain to you the concept of flat panel image receptors,

how they work and which different types there exist.

Then we will discuss the problem of defect pixels that appear in the context of flat panel detectors

and what type of interpolation techniques can be applied to eliminate the defect pixels.

And for that purpose we will describe algorithms that work in the spatial domain,

so directly on the image data.

And we will discuss algorithms that work in the frequency domain,

so we look at the Fourier transform.

And for that reason I briefly summarize what the Fourier transform is,

what it does and what properties are required for us.

For the students that attended lectures on systems and signals on systems,

this should not be an issue at all.

For the others it's a little refresher course or something like that.

And then we will talk about different algorithms in the spatial domain

and in the frequency domain using the Nyquist sampling theorem as a basis for the algorithm

and using certain symmetry properties of the Fourier transform of real valued signals.

And at the end as usual a few take homes and a few pointers through further readings.

That's the story for today and tomorrow, the program.

The purpose of digital radiology or radiography is to replace the good old film sheets

and the light box with digital systems.

So if you go to a fully digital radiology department there should be no light boxes anymore and films.

They have highly developed monitors, so they have special medical monitors

to inspect their digital data and the question is how do we get the digital data?

There are different ways.

One technology that was heavily used until the beginning of the century were the image intensifiers.

We know how these image intensifiers work in principle.

We also know what type of artifacts are implied by image intensifiers

and how these can be compensated by using algorithms.

And the second generation of detector technology that is currently state of the art

are the flat panel detectors that have a lot of advantages compared to the image intensifiers.

Basically the introduction of the flat panel detector technology has implied tremendous changes

in the radiology departments and they are today well established in radiography.

If you want to see the thorax or basic x-ray imaging you will be faced with systems that have digital sensors.

If you go into the cardiology department all these modern systems they are using flat panel technology

and also in mammography that's the imaging of the female and even male breast.

There are even males having problems with the mama.

They use flat panel detector technology today.

Good.

So there was a tremendous change. Don't read these things.

This is just support information if you print out the slides and you want to read a little bit beyond the videotapes.

In the radiography department they capture standard x-ray images.

And how does that work?

Basically here you have your x-ray system and the x-ray tube is mounted.

I should point with my fingers I learned because the laser pointer is not visible for the international community.